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Diffstat (limited to 'vendor/unicode-normalization/src/lookups.rs')
-rw-r--r-- | vendor/unicode-normalization/src/lookups.rs | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/vendor/unicode-normalization/src/lookups.rs b/vendor/unicode-normalization/src/lookups.rs new file mode 100644 index 000000000..ea7a96c49 --- /dev/null +++ b/vendor/unicode-normalization/src/lookups.rs @@ -0,0 +1,138 @@ +// Copyright 2019 The Rust Project Developers. See the COPYRIGHT +// file at the top-level directory of this distribution and at +// http://rust-lang.org/COPYRIGHT. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +//! Lookups of unicode properties using minimal perfect hashing. + +use crate::perfect_hash::mph_lookup; +use crate::tables::*; + +/// Look up the canonical combining class for a codepoint. +/// +/// The value returned is as defined in the Unicode Character Database. +pub fn canonical_combining_class(c: char) -> u8 { + mph_lookup( + c.into(), + CANONICAL_COMBINING_CLASS_SALT, + CANONICAL_COMBINING_CLASS_KV, + u8_lookup_fk, + u8_lookup_fv, + 0, + ) +} + +pub(crate) fn composition_table(c1: char, c2: char) -> Option<char> { + if c1 < '\u{10000}' && c2 < '\u{10000}' { + mph_lookup( + (c1 as u32) << 16 | (c2 as u32), + COMPOSITION_TABLE_SALT, + COMPOSITION_TABLE_KV, + pair_lookup_fk, + pair_lookup_fv_opt, + None, + ) + } else { + composition_table_astral(c1, c2) + } +} + +pub(crate) fn canonical_fully_decomposed(c: char) -> Option<&'static [char]> { + mph_lookup( + c.into(), + CANONICAL_DECOMPOSED_SALT, + CANONICAL_DECOMPOSED_KV, + pair_lookup_fk, + pair_lookup_fv_opt, + None, + ) + .map(|(start, len)| &CANONICAL_DECOMPOSED_CHARS[start as usize..][..len as usize]) +} + +pub(crate) fn compatibility_fully_decomposed(c: char) -> Option<&'static [char]> { + mph_lookup( + c.into(), + COMPATIBILITY_DECOMPOSED_SALT, + COMPATIBILITY_DECOMPOSED_KV, + pair_lookup_fk, + pair_lookup_fv_opt, + None, + ) + .map(|(start, len)| &COMPATIBILITY_DECOMPOSED_CHARS[start as usize..][..len as usize]) +} + +pub(crate) fn cjk_compat_variants_fully_decomposed(c: char) -> Option<&'static [char]> { + mph_lookup( + c.into(), + CJK_COMPAT_VARIANTS_DECOMPOSED_SALT, + CJK_COMPAT_VARIANTS_DECOMPOSED_KV, + pair_lookup_fk, + pair_lookup_fv_opt, + None, + ) + .map(|(start, len)| &CJK_COMPAT_VARIANTS_DECOMPOSED_CHARS[start as usize..][..len as usize]) +} + +/// Return whether the given character is a combining mark (`General_Category=Mark`) +pub fn is_combining_mark(c: char) -> bool { + mph_lookup( + c.into(), + COMBINING_MARK_SALT, + COMBINING_MARK_KV, + bool_lookup_fk, + bool_lookup_fv, + false, + ) +} + +pub fn stream_safe_trailing_nonstarters(c: char) -> usize { + mph_lookup( + c.into(), + TRAILING_NONSTARTERS_SALT, + TRAILING_NONSTARTERS_KV, + u8_lookup_fk, + u8_lookup_fv, + 0, + ) as usize +} + +/// Extract the key in a 24 bit key and 8 bit value packed in a u32. +#[inline] +fn u8_lookup_fk(kv: u32) -> u32 { + kv >> 8 +} + +/// Extract the value in a 24 bit key and 8 bit value packed in a u32. +#[inline] +fn u8_lookup_fv(kv: u32) -> u8 { + (kv & 0xff) as u8 +} + +/// Extract the key for a boolean lookup. +#[inline] +fn bool_lookup_fk(kv: u32) -> u32 { + kv +} + +/// Extract the value for a boolean lookup. +#[inline] +fn bool_lookup_fv(_kv: u32) -> bool { + true +} + +/// Extract the key in a pair. +#[inline] +fn pair_lookup_fk<T>(kv: (u32, T)) -> u32 { + kv.0 +} + +/// Extract the value in a pair, returning an option. +#[inline] +fn pair_lookup_fv_opt<T>(kv: (u32, T)) -> Option<T> { + Some(kv.1) +} |